Author/Editor     Drzewiecki, Gary; Li, John KJ; Knap, Bojan; Južnič, Susara; Južnič, Gojmir; Noordergraaf, Abraham
Title     Cardiac hypertrophy and shape: a noninvasive index?
Type     članek
Source     J Cardiovasc Diagn Proced
Vol. and No.     Letnik 13, št. 3
Publication year     1996
Volume     str. 193-8
Language     eng
Abstract     The wall thickness W of the left ventricle is examined as a possible long-term index of contractility. Two possible stimuli for increases in W are extrinsic pressure overload and cardiomyopathy. This results in the concentric hypertrophy growth pattern. This pattern of hypertrophy has been successfully explained using the wall stress theory of hypertrophy. In this study, a mathematical model of cardiac growth is used to solve directly for the change in W with respect to myocardial loss of contractility. This model supports the theory that rate of myocardial oxygen consumption is regulated at the myocyte in the face of extrinsic overloads or intrinsic functional impairment. It is found that W increases for both normal physiological hypertrophy and cardiomyopathy, as observed in the clinic. To differentiate abnormal function, the ventricular shape is examined with respect to its similarity to a perfect sphere. It is found that cardiomyopathy induces a more spherical shape of ventricle with respect to a normal ventricle and exercise-trained hypertrophy. It is proposed that ventricular wall thickness or wall thickness to diameter ratio together with comparison to a spherical shape may be a useful indicator of chronic cardiomyopathy.
Descriptors     HEART HYPERTROPHY
MYOCARDIAL CONTRACTION
OXYGEN CONSUMPTION
VENTRICULAR DYSFUNCTION, LEFT
CARDIOMYOPATHY, HYPERTROPHIC
MODELS, THEORETICAL